Category: sugar
Aliases: HFCS, HFCS-55, HFCS-42, Glucose-fructose syrup, Isoglucose, Fructose-glucose syrup, Maize syrup
Enzymatically isomerized cornstarch hydrolysate: a free-monosaccharide syrup, not a glycoside, so it requires no luminal hydrolysis. HFCS-55 (beverage grade) is ~55% [[fructose]] / 42% [[glucose]] of dry solids, near-identical to sucrose's 50/50 split but with the monosaccharides unbound. Glucose is taken up via SGLT1/GLUT2 and raises blood glucose + [[insulin]]; fructose enters enterocytes/hepatocytes via GLUT5 and is trapped by ketohexokinase (fructokinase) as fructose-1-phosphate, bypassing PFK-1's rate-limiting step -> unregulated trioses feeding de novo lipogenesis, plus ATP depletion driving urate generation (hyperuricemia). Net sweetness ~ sucrose (~1.0x). GRAS in the US; no separate EU E-number (regulated as a sugar/food ingredient; HFCS-55, being fructose-predominant, is labeled 'fructose-glucose syrup' in the EU, whereas glucose-predominant grades like HFCS-42 are labeled 'glucose-fructose syrup').